Battle of Sankoyama

The Battle of Sankoyama (1576) was a battle of the Sengoku Period fought between the Toyotomi and Mori clans during the Sengoku Jidai. Hideyoshi Toyotomi sent his general Hanbei Takenaka to crush Motonari Mori, but the large Toyotomi army was itself destroyed by the Mori.

Background
Starting in 1576, the Oda forces campaigned against the Mori after their shogun Yoshiaki Ashikaga pleaded for the assistance of Motonari Mori in fighting Nobunaga Oda and helping him back to power. Nobunaga fought the Mori navy at the First Battle of Kizugawa in Osaka Bay, which was a defeat; the Mori defeated Nobunaga's vassal Hideyoshi Toyotomi at the Battle of Kozuke Castle in another battle. However, the warring continued as the Mori continued to pose a threat to Nobunaga's west while the Saika and Uesugi threatened him from the easy. Hideyoshi sent his general Hanbei Takenaka with 5,580 Toyotomi troops to crush the Mori clan, invading their domains. The Toyotomi army moved against the Mori clan's forces at Sankoyama in Bitchu Province, and the Toyotomi met Motonari's 4,050 Mori troops on a plain. The Mori army was smaller, but its warriors were stronger than those of the Toyotomi army.

Dispositions
Motonari Mori rallied his forces before they fought, and he deployed them in a standard formation three lines deep. The Toyotomi army had the high ground, and they were overstretched. Motonari was not intimidated by the sheer size of the Toyotomi, and he allowed the Toyotomi army to maneuver into a diagonal formation that threatened his flank. He sent out a force of troops on his right flank to attack the Toyotomi's flank, and the Toyotomi army maneuvered again, moving their forces to the hill.

First Phase
The first phase of the battle began with the Mori attack on the Toyotomi flank. The Mori forces engaged the Toyotomi infantry as they were marching towards their designated defensive positions, and the Toyotomi forces withdrew. The Mori left flank proceeded to assault the Toyotomi position there, and the Toyotomi right flank charged up the hill from the right to dislode the Toyotomi army. However, the routing Toyotomi units on the right flank rejoined the fight, so the Mori were forced to charge downhill and assault them. The Mori routed them again and moved uphill, but the units returned for a final time. The Mori again routed the Toyotomi flank, finishing them for the last time.

Second Phase
The second phase involved the Mori main force's attack against the Toyotomi main force after the first phase ended. When the Mori flank units routed the Toyotomi detachments and began their attack uphill, Motonari decided to follow up the attack by advancing his main force towards. The Mori main force attacked the Toyotomi center, and Motonari was briefly involved in combat with the Toyotomi army before he backed up to a safe distance as his forces fought the Toyotomi in bloody melee. The Mori forces' combined assault drove off the Toyotomi army, and the Mori emerged victorious over the Toyotomi clan. 401 Mori and 2,692 Toyotomi were killed, and the Toyotomi were forced to retreat again.